Wednesday, February 13, 2008

Creatures of the night emerge

Our noon position: Latitude: 35 31.691 North, Longitude: 141 00.317 West

Day 2 of our second research study. Just passed mile 3,000 of our journey! We’ve learned from past experience that its unwise to celebrate ideal weather conditions prematurely… with bated breath, we continue to be floored by the calmest seas yet, making our research a dream. And a catastrophe.

Today’s daytime sample yielded something we haven’t yet seen – numerous microfilaments and tiny line fragments embedded in the net of our sampling tubes. These fibers are the main type of debris found in our subsurface trawls, up to 100 meters deep. The calm waters allowed these fragments to float to the surface, where they lodged in our nets. The small particle size that we continue seeing here in this “inner ring” of the gyre may mean that this debris has been kicking around here for some time, swirling around in an endless spin cycle where it degrades into tiny, fouled fragments.

We mentioned finding a surprising quantity of small, deeper sea fish in our night sample. Here’s the image we meant to post yesterday – “Myctophid Soup”. Myctophids, also known as “lantern fish” are generally found at 100 meters, and only come to the surface at night to feed.

The second photo here shows the total amount of fish and plastic we pulled up in our sample. We found this one of the more startling images yet – these creatures are surfacing to feed - amongst increasing amounts of plastic.

Here are some responses to yesterday’s questions:

Students from West Lafayette asked if the majority came from large scale dumping directly into the ocean, or runoff from street litter. According to data collected from coastal cleanups, 80% of the marine debris that washes up on beaches originates from land based sources – when street litter washes out to sea through storm drains, “urban runoff”. Out here, much of the identifiable debris were seeing comes from the fishing industry – fishing floats, ropes, net fragments, and other derelict fishing gear. The majority though is made up of plastic fragments.

To Lcander, your students are not alone in having a hard time grasping how immense this area is. It almost takes being here to fully get it, but as this isn’t logistically possible for everyone, the next best thing is for us to try and convey this to you. Let us know where you are, and perhaps we can even visit your school in person.

Dawn was wondering if we can track the origin of this debris, or if the problem is too vast. Scientists have developed current models that help us to predict where debris travels once it enters the ocean. As for tracking the origin, Dr. Curtis Ebbesmeyer (check out the Beachcombers' Alert ) can track debris with markings and some unique items are traceable, while Dr. Hideshige Takada (check out International Pellet Watch) has tracked pre production plastic pellets by the pollutants they absorb. Plastic Chemists indicate that production plastics have a unique chemical marker that is specific to various manufacturers and manufacturing processes. This "fingerprint" can be recognized by the technique of gas chromatography. The National Oceanic Atmospheric Administration is developing a "taxonomic key" to identify which fisheries derelict fishing gear originates from. NOAA has been taking data based on various characteristics of derelict fishing gear recovered from the Northwest Hawaiian Islands with the hope that it will lead to a way to identify the biggest polluters and work with them to decease the amount of derelict fishing gear floating in the North Pacific.

Kaisa, you and your classmates had another excellent question about recycling that we’ll address tomorrow – it deserves a separate post.

We just launched trawl number 7 – we’ll be sampling throughout the night, and sure to find more interesting specimens....

Aloha and gracias from the Captain and Crew of the ORV Alguita!

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